ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Division Spotlight
Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
Meeting Spotlight
Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
Latest Magazine Issues
Jul 2024
Jan 2024
Latest Journal Issues
Nuclear Science and Engineering
August 2024
Nuclear Technology
Fusion Science and Technology
Latest News
Vogtle-3 shuts down for valve issue
One of the new Vogtle units in Georgia was shut down unexpectedly on Monday last week for a valve issue that has since been investigated and repaired. According to multiple local news outlets, Georgia Power reported on July 17 that Unit 3 was back in service.
Southern Company spokesperson Jacob Hawkins confirmed that Vogtle-3 went off line at 9:25 p.m. local time on July 8 “due to lowering water levels in the steam generators caused by a valve issue on one of the three main feedwater pumps.”
D. J. Euh, B. G. Huh, B. J. Yun, C.-H. Song, I. G. Kim
Nuclear Technology | Volume 164 | Number 3 | December 2008 | Pages 368-384
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT164-368
Articles are hosted by Taylor and Francis Online.
The reflood rate in a core is an important parameter for core cooling during a large-break loss-of-coolant-accident (LBLOCA) reflood period, and it strongly depends on the thermal-hydraulic conditions in the downcomer. During this period, downcomer boiling has an important influence on the transient behavior of a postulated LBLOCA because it can degrade the hydraulic head in a downcomer and consequently affect the reflood flow rate for core cooling. Although it is recognized that downcomer boiling is critical to correctly predict the reflood phenomena of an LBLOCA transient, especially for a direct vessel injection adapted system like the advanced power reactor APR1400, the amount of experimental data and code assessment in this area is relatively limited. To improve the state of knowledge relative to downcomer boiling, a test program at the Downcomer Boiling (DOBO) facility is progressing for the reflood phase of a postulated LBLOCA. The DOBO facility was designed to meet a full scale for the height and gap of a reactor downcomer. The DOBO test revealed a strong multidimensional boiling behavior, which induces the need for performance evaluation of the best-estimate codes that are used to analyze a nuclear reactor's thermal-hydraulic safety, since they have mostly been used for one-dimensional system behavior. In this study, RELAP, MARS, and TRACE are evaluated by using measured two-phase-flow data. Based on the assessments, the modeling capability and weak points of the safety analysis codes are addressed for multidimensional downcomer boiling phenomena. Two models for a downcomer are considered to assess the codes for the DOBO tests, which are also applied to a plant analysis.